Hi Pilou,

> So we must have at any time same number of segments
> between 2 curves lofted?

Only if you want to have control over which specific parts of each curve is connected to the other.

If you have the same number of segments, then each segment is matched to the other corresponding segment - for example segment #1 on the first curve is matched to segment #1 on the second curve.

You can still make a loft between curves that have a different number of segments between them, but when you do that the matching will happen by a distance traveled along each curve, which will not necessarily match one small feature like a rounded corner with another rounded corner of a different length on the other curve. Having connections just by traveled length can make for a kind of twisting effect when there are small localized features between the curves.

See this previous post for some more illustration and explanation:
http://moi3d.com/forum/index.php?webtag=MOI&msg=4214.1


> So why the mecanism is not automatic (about number of segments) ?

There is an automatic mechanism that will be used if there is a different number of segments, but remember that MoI does not have artificial intelligence and so it's not really able to analyze curves and identify particular small pattern features that you would like to have matched - for example it's not able to just look at 2 long curves and automatically recognize that you'd like to have 2 smaller sub-regions of different lengths (like the rounded corners in this case) to be matched with each other.

But if you have the same number of segments between the curves, then MoI will be able to match things segment to segment.

So it's not required to have the same number of segments, but it can help to have it if you want to have some particular zone of each curve matched to the other instead of just having them connected by length traveled along the curve.


The other way you can control these things is to do lofts between smaller sections at a time, instead of doing the loft between 2 long curves that have various small sub features within them like rounded corners. If you do the loft between smaller sections (like between each separate feature), that can help you to control how the curves are being connected together instead of them being connected just by distance traveled along each curve.


- Michael